The present invention relates to a coated chewing gum containing active materials such as prophylactic, nutritional or therapeutic substances including, for example, vitamins and minerals. More particularly, the present invention relates to a coated chewing gum such as a gumball comprising a gum center and an exposed outer shell wherein at least one active material is contained in the chewing gum core, and at least one other active material is contained in the coating (or outer shell).
Chewing gums in various forms such as slab, stick, tablet, block or ball shapes, and methods for producing the same, are known in the art. Conventional chewing gum generally includes a gum base to which is added water-soluble sweeteners, emulsifiers, mono- and di-glycerides, flavorings and colorants. For example, the water-soluble sweeteners typically include various sugars such as sucrose and dextrose, corn syrup, sorbitol and/or artificial sweeteners such as sodium or calcium saccharin, cyclamates and aspartame. A typical emulsifier for use in chewing gum is, for example, lecithin.
Chewing gums are generally prepared by melting a gum base in a kettle, mixing corn syrup or other softeners with the gum base, followed by adding solid sweeteners, flavorings, colorants and other additives. The chewing gum is then removed from the kettle, and formed into the desired shape. The result of such a process is typically a chewing gum product that is a continuous mass of gum base with the sweeteners, softeners, and other additives dispersed therein.
The use of a chewing gum product to deliver active materials, that is, using a gum base as a carrier for the active materials, is known in the art. For example, U.S. Pat. No. 4,238,475 to Witzel et al. discloses a chewing gum product capable of releasing finely divided water-insoluble therapeutic materials. The therapeutic components to be released from the chewing gum may comprise beneficial materials such as dicalcium phosphate, antacids, vitamins, drugs and the like. The disclosed chewing gum includes finely divided water-insoluble therapeutic materials coated with a water-soluble coating agent such as gum arabic so as to prevent resorption of the water-insoluble therapeutic material back into the gum base. The coated material is dispersed, along with a relatively water-insoluble phase comprising gum base, in a water-soluble phase comprising a softener, to form the chewing gum. The chewing gum may then be formed into such shapes as sticks, cubes, pillows and balls, and may optionally include a sugar or sugarless coating or shell. However, the outer coating or shell only provides additional flavor and/or sweetness to the chewing gum, protects the soft gum center and improves overall shelf-life of the gum; it does not include additional active materials.
U.S. Pat. No. 4,154,814 to Hand et al. discloses a therapeutic chewing gum comprising high concentrations of sodium and potassium salts in a critical ratio. The chewing gum composition comprises an insoluble gum base for use as a delivery vehicle for vitamins and the sodium and potassium salts. For example, it is described that such vitamins as ascorbic acid (Vitamin C), thiamine mononitrate (Vitamin B-1) and riboflavin (Vitamin B-2) may be added to the gum base.
Similarly, U.S. Pat. Nos. 3,011,949 and 3,075,884, both to Bilotti, disclose methods for promoting the release of active ingredients, such as dicalcium phosphate, powdered vitamins and antacid powders, from chewing gum. In the described processes, the individual solid particles of the active ingredients to be released from the chewing gum are coated with wet sugar and are then incorporated into a slab-shaped chewing gum.
U.S. Pat. No. 3,075,884 states that a practice of the prior art was to incorporate active ingredients into a hard candy shell, as opposed to the core, of a coated chewing gum. The active ingredients were incorporated into the shell because it had theretofore not been possible to incorporate them into the gum base while ensuring ready release of the active ingredients from the gum base. It states that the practice had been to deposit the active ingredients on the exterior of a gum nugget or center, usually with an underlying thin layer of sugar, and to coat the unit with a final layer of hard sugar. The product is referred to as "candy coated gum" and is described as releasing the active ingredients from the hard shell into the mouth before the active ingredients are chewed into the gum base. However, the method of incorporating active ingredients into the gum base as described in the patent rejects the hard candy shell in favor of the gum base as the preferred location of the active ingredients.
Presently, active materials such as vitamins and other nutritional and therapeutic substances are typically administered in the form of either a liquid or a chewable or non-chewable tablet, capsule or caplet. For example, in the case of vitamins, the vitamins are generally administered in the form of either a chewable, compressed tablet (typical of children's formulations) or in the form of a compressed, non-chewable tablet (typical for adult formulations). However, for a great number of children, for instance in the 2-4 and 4-12 year old age groups, vitamins in the form of chewable or non-chewable tablets may be either impractical or not preferred. For example, while many of the older children may have "outgrown" the chewable vitamin tablets currently on the market, they may still have difficulty swallowing the regular, larger-sized vitamin tablets that are intended for adults. Additionally, it is generally conceded by the medical profession that small, continued doses of active nutritional and therapeutic substances such as vitamins are of greater therapeutic and nutritional value than larger single doses. A multi-vitamin containing chewing gum may therefore address both the concerns of providing vitamins to children in a practical form, while simultaneously providing maximized therapeutic and nutritional effect.
Chewing gums are an answer, but the difficulty in producing effective and commercially desirable products has precluded the use of vitamin-containing chewing gums. While chewing gum products have been produced that contain one or several active ingredients, it has previously not been possible to include the desired multiple active materials into a chewing gum. The difficulties encountered include incorporating incompatible compounds into the same product, providing for effective (and especially cost effective) release of the active materials during chewing of the gum, and maintaining the texture and desirable characteristics of the gum.
Specifically, there has been a substantial difficulty in preparing vitamin-containing chewing gums that contain some or all of the desired active materials. Such difficulties include masking the undesired flavor of some of the active materials (such as minerals that have an unappealing taste). It has also been difficult incorporating multiple generally incompatible active materials into a gum base in a compatible manner without adversely altering the consistency and chewability of the chewing gum. In particular, it has been especially difficult to incorporate fat-soluble vitamins or other fat-soluble substances into general carrier compounds, much less into chewing gum. This is aggravated by the fact that chewing gums in particular, as carriers for active materials, pose the additional problem of decreasing the release level of the active materials from the chewing gum base.